Specific heat and transport study of the co-existence of charge-density-wave and weak ferromagnetism in

✍ Scribed by N.S. Kini; A. Bentien; S. Ramakrishnan; C. Geibel

• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 170 KB
• Volume: 359-361
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/j.physb.2005.01.395

✦ Synopsis

Monoclinic BaIrO 3 was reported to display simultaneous onset of charge density wave transition (CDW) and weak ferromagnetic ordering of Ir moments at T c ¼ 175 K: In this work, we present heat capacity, resistivity, thermopower and thermal conductivity measurements on a high-quality polycrystalline BaIrO 3 sample. The specific heat evidences a well defined mean field like anomaly, much larger than that reported for a single crystal, and at a slightly higher T c ¼ 183 K: The increase of the resistivity below T c is also much larger than in previous investigation, and the semiconducting behavior at low temperature is much more pronounced. The onset of the CDW leads to a strong increase of the thermopower, from a few mV=K above T c up to nearly 300 mV=K at 70 K, supporting a strong decrease of the charge carrier density and the opening of a gap at T c : In contrast, no anomaly is observed at T c in the thermal conductivity, which is dominated by phonon contributions.